RM-235
System module and user interface
Signals with different frequencies take different paths, therefore being handled by different components.
The principle of GSM and WCDMA is the same.
Transmitter (TX)
The digital baseband signal (eg. from the microphone) is converted to an analogue signal, which is then
amplified and transmitted from the antenna. The frequency of this signal can be tuned to match the bandwith
of the system in use (eg. GSM900).
The transmitter functions are implemented in the RF ASIC.
Even though the GSM and WCDMA signals are sent via different components, the principles of the transmission
is the same.
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COMPANY CONFIDENTIAL
Issue 1
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